The excellent anchor rod of prestressing force
The excellent anchor rod of prestressing force: From have no Zong rib thread steel metal rod body and spherical tray , the attachment composition of reducing hindrance washer, metal flat washer and excellent damping nut ,Its performance conducted standard MT146 .2-2002 ,Thread steel rod body from unidirectional left Xuan have no Zong rib thread steel system becomes ,End department levels to cut ,Tail processing becomes the thread that may join nut ,In it is dozen that the torque that sets takes off nut damping do not drive , nut damping begins after opening to give anchor rod to exert installation stress. Anchor rod installation stress is in 4 generally ~ 5 tons.
strong point:Can not only exert greater prestressing force and may raise considerably to protect speed, protects strength stability , can improve tunnel obviously to protect effect. Install anchor rod the standardization of prestressing force, is easy to ensure to pay to protect strength and construction quality inspection.
Anchor rod flexible of prestressing force protects method in order to pay a kind of new that protects deep base hollow protect form ,Protect method with other to compare ,This method is because of its economy ^dependable: Construction is convenient , it is little to warp , protects the notable advantage of depth such as is big, in Chinese rock earth project field, already get extensive application. This writing uses nonlinear limited Yuan method to protect for anchor rod of prestressing force to carry out value analysis research ,In order to the application that this technology gets more extensively offers relatively scientific basis. First of All protects with limited Yuan method for anchor rod flexible of prestressing force to carry out value to imitate. By studying the deformed, anchor rod of base hollow the distribution law that gets force state and axle force, analyse the mechanics performance that anchor rod flexible of prestressing force protects. Secondly ,By protecting with earth nail to carry out value analysis comparison ,The control for base hollow warps influence as well as the analysis that gets force condition, know further the role mechanism that anchor rod flexible of prestressing force protects. The Third ,By protecting for anchor rod flexible of prestressing force to carry out structure to change parameter analysis ,Have studied anchor rod length ^Anchor rod protects inclination, anchor rod arrangement span and anchor rod length arrangement, the change of way as well as facing thickness warps for base hollow the influence with anchor rod axle force. at Last carries out limited Yuan value analysis for project example, with the result of actual measurement carry out comparison. Study mainly that conclusion is as follows: 0 anchor rod of prestressing force protect the face of land and the horizontal displacement of next base hollow to subside to submit curve distribution, and earth nail it is similar to protect. Horizontal displacement biggest value occurs in base hollow end face, reduce gradually with the increase of depth; The face of land subsides biggest value occurs in hollow wall place, follow is away from hollow wall to be away from increase reduces. 1 anchor rods are in free part scope internal shaft , force is identical, follow open to dig depth to deepen, free part axle force increase; Anchor rod anchor firmly free part and the axle force of part are linked , axle force is biggest, its force of rear axle reduces gradually, end is 0. 2 anchor rods the size of prestressing force exerted is great for base hollow displacement influence. Along with the increase of anchor rod prestressing force, base hollow displacement reduces substantially, but when after prestressing force exerts certain big value, the influence for base hollow displacement has less range. 3 is under same terms ,Even if earth nail span changes little ,Earth nail protects next base hollow displacement, the displacement protected than anchor rod of prestressing force is big ,Evidently for the strict base of deformed requirement, hollow, anchor rod of prestressing force protects since having exerted prestressing force, protecting than earth nail can efficiently control base hollow displacement more. 4 passes through the structural parameter for that anchor rod of prestressing force protects to carry out change research ,Suggest the arrangement way of anchor rod to go up each row anchor rod to take the length of becoming , or do top anchor rod length is some wait to determine the nature somewhat law. 5 is analysed through the calculation for project example, have verified model to establish reasonability as well as the feasibility of protecting deep base hollow with anchor rod of prestressing force.